We have a Vaillent combi which does a fabulous job. Definitely don't scrimp. It will pay for itself. A soak in the bath is a very important matter for me. In my last house, we had a lovely big corner bath, and the cylinder couldn't fill it, so I never had a deep bath - I was so happy when we replaced it for a combi and I could enjoy a full bath.

Never had a leak but it should be fairly easy to narrow down where it is by isolating the different runs. And if you do have a leak under the floorboards, you're going to want to know about it sooner rather than later. Pipes can still leak, however the water is heated. With a combi boiler, you can see very easily if you are losing pressure and might have a leak.

Combis are fine until the sealed system springs even the tiniest of tiny leaks, then they lose pressure and don't work. Then you have the issue of trying to figure out where the leak is coming from ... and that may mean pulling up all the floorboards and generally dismantling your house to find a mere drip.

landrover - we may have just been unlucky, it was a poncey expensive 'new build' so there was no need to skimp on the original boiler and then we replaced it, at our own expense, for another one which we had researched, but still didn't seem much better!

I never had a decent bath in the 10 years we lived there - the bliss when we moved into a rented property and could get a fabulous hot bath!! Now in our next house (also new build) we have a combination boiler and hot baths .............. just off for a hot bath now .

I think some people are confused. Conventional boilers and cylinders don't heat by the immersion heater it's supplemental to the boiler heating the water and storing it in the cylinder. Immersion heater works as an additional heating element to the boiler. Not all cylinders have them, but they are useful if boiler isn't working as they can work independently. A similar solution would be having an electric shower.

Ragwort, Im guessing that Most had a Combi that was capable of that amount of work. The combis have different size outputs so you have to make sure that you have the right size combi for the amount of radiators etc. Im guessing that maybe your combi wasn't the right size for your house (new build skimping maybe?) Only guessing of course!! (I have not a lot of combi experience

I installed a (reasonably expensive at the time) Worcester Bosch combi boiler in my flat 14 years ago and it is still going strong, had never gone wrong and the engineer tells me is still very current by today's standards. A very good brand. We have a Vaillant in our house but the Worcester is better.

12 radiators over 3 floors, 3 bathrooms with 1 bath & 2 showersWe have a good quality Combi and would never have anything else.

If the boiler failed (which it never has) we would use kettles until it was fixed and we would get it fixed within a few days. I'm not going to give house space to an inefficient immersion heater just in case the boiler breaks! The boiler is 15 years old now and is serviced every year.

We've just replaced a 40+ year old conventional boiler with a combi. That, and having all our sash windows replaced with look-alike double glazed units, has taken over 150 quid a month off our fuel bills.

We only put the hot water on in the morning and the evening (on programmer) on our conventional boiler & megaflow and we haven't yet run out of hot water even when we had 15people here over Christmas. It heats up very fast (about 20mins if a top up is needed) and the modern cylinder stays warm all day. Gas bills aren't too bad even though until we finish the renovations it's a bit like heating a giant leaky sieve. Can't wait for the windows & insulation to be finished. Whatever way you go getting a decent programmer, room stat and thermostatic radiator valves means that you use your boiler much more efficiently.

I have 12 rads in a 4 bedroom, 1 bathroom house.I have a lakeland heated airer so don't need the airing cupboard for drying.I just wanted to avoid the mess (and sorting out the loft) involved in removing the tanks.

Depends on how big your property is - I think combi's were originally invented for use in flats although am sure they have moved on by now.

We had a combi boiler when we bought our bungalow....hated it and missed my airing cupboard - we went back to a conventional boiler and it is so much better. I like my baths very deep and very hot and the combi just didn't cut it for me.

My gas bills are much less now that I have a combi boiler and the constant hot water is great. I do agree about the reduced water flow in running a bath, it takes forever but hey, not a problem if you prefer showers.